1. Field of the Invention
The present invention relates to a touch screen panel for an image display device or the like.
2. Description of Related Art
A touch screen panel is an input device that allows a user's instruction to be inputted to an image display device or the like by selecting an instruction content displayed on a screen of the image display device with a user's finger or an object.
To this end, a touch screen panel is provided on a front side of an image display device to convert a contact position into an electrical signal. At the contact position, a user's finger or an object is directly in contact with the touch screen panel. Accordingly, an instruction content selected at the contact position is inputted as an input signal to the image display device.
The applications for a touch screen panel have gradually expanded because it can be used to operate an image display device and replace a separate input device (e.g., keyboard or mouse) connected to the image display device.
Touch screen panels are classified into a resistive overlay type touch screen panel, an infrared beam type touch screen panel, a capacitive overlay type touch screen panel, and the like.
Among these touch screen panels, the capacitive overlay type touch screen panel converts a contact position into an electrical signal by sensing a change in capacitance formed between a conductive sensing pattern and another sensing pattern adjacent to the conductive sensing pattern, a ground electrode or the like when a user's finger or an object is in contact with the touch screen panel.
To determine a precise contact position on a contact surface, sensing patterns include first sensing patterns (e.g., X-patterns) formed along a first direction to be connected to each other, and second patterns (e.g., Y-patterns) formed along a second direction to be connected each other.
The first and second sensing patterns are generally formed from the same layer of material. In this case, sensing patterns of the first or second sensing patterns arranged on the same X or Y line or direction are connected by forming separate connection patterns through contact holes formed in an insulating layer formed on the sensing patterns. Therefore, the number of masks utilized during fabrication may be increased, and a fabrication process may be complicated.
In addition, the first and second sensing patterns are connected to position detecting lines by metal patterns at edge portions of regions in which the first and second sensing patterns are formed, respectively.
The metal patterns connect the first and second sensing patterns to the position detecting lines. To improve reliability of the touch screen panel, it is important to maintain the connection state of the metal patterns.